The field of genetics in dermatology has progressed immensely in the last 20 years and has strongly influenced the practice of dermatology. Most known single gene disorders, such as epidermoloysis bullosa, have been mapped to a particular chromosomal region and in many cases, the causative genes have been identified. However, more common diseases that are polygenic in origin such as atopic dermatitis remain a challenge to decipher. In addition, there still remain several monogenic disorders in which the underlying genetic basis is unclear.